The present invention relates to a marine engine propelling apparatus which is mounted, for example, to an outboard portion at a rear end of a boat.
A marine engine propelling apparatus is mounted to an exterior portion at a rear end of a boat used, for example, for fishing or cruising. There exist a variety of engine propelling apparatuses according to the size of the boat or the height of the rear end of the boat as measured from the water surface, etc.
Japanese Laid-Open Patent Publication 2013-519574 discloses a large marine outboard motor. The large marine outboard motor 110, as shown in FIG. 15, is equipped with an engine 111, a first transmission 112A, a second transmission 112B, a third transmission 112C, a propeller shaft 122, and a propeller 127. A plurality of power transmission routes D100 to D104 exist between the engine 111 and the propeller 127. In the power transmission route D100, power is transmitted substantially in the horizontal direction, which is the direction of the rotation axis of the crankshaft 111C of the engine 111. In the power transmission route D101, power is transmitted substantially in the vertical direction from the rear end of the engine 111 the end facing away from the boat in FIG. 15 to the second transmission 112B through the first transmission 112A. In the power transmission route D102, power is transmitted substantially in the horizontal direction. In the power transmission route D103, power is transmitted substantially in the vertical direction from the second transmission 112B to the third transmission 112C. In the power transmission route D104, power is transmitted substantially in the horizontal direction from the third transmission 112C through the propeller shaft 122, i.e., in the direction of the rotation axis of the propeller shaft 122. Thus, the power transmission routes are configured to form an S-shaped route. The motor 110 is mounted to the rear end of the boat 1 via a right-left steering means 132 for swinging the position of the motor 110 to the right or left with respect to the longitudinal axis of the boat 1.